Answer:
y=2
Step-by-step explanation:
7y-1=13
+1 +1
7y=14
/7 /7
y=2
If triangle ABC is congruent to triangle DEF, then EF = BC = 27
This is because BC and EF are the last two letters of ABC and DEF respectively. They match up and correspond, being congruent by CPCTC
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Similarly, if triangle ABC is congruent to triangle DEF, then angle D = angle A = 49 degrees
The letter D and the letter A are the first letters of DEF and ABC respectively. So they match up and are congruent by CPCTC
CPCTC = Corresponding Parts of Congruent Triangles are Congruent
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So in short, the answer is choice B) 27; 49
8r^6s^3 - 9r^5s^4 + 3r^4s^5 - (2r^4s^5 - 5r^3s^6 - 4r^5s^4) =
8r^6s^3 - 9r^5s^4 + 3r^4s^5 - 2r^4s^5 + 5r^3s^6 + 4r^5s^4 =
8r^6s^3 -5r^5s^4 + r^4s^5 + 5r^3s^6 <==